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Biomedical subjects

M W Hess

Publications and source records attributed to M W Hess.

At least 91 records · Page 5Linked to original sources
PubMed1976

Nonspecific esterase activity in T cells.

Acid alpha-naphthyl acetate esterase activity characterizes the majority of peripheral T cells in mice. In addition to the simplicity of the cyto- or histochemical demonstration of esterase activity and the fact that this method may be applied to tissue sections and smears, the present study indicates that combination with lymphocyte surface markers may offer an important approach to the examination of differentiation pathways of peripheral T cells.

Animals↗
PubMed1976

Problems relating to immunoselection of leukemias.

Problems relating to immunoselection of neoplastic, in particular leukemic, cell lines are reviewed. Since there is ample evidence that specific immune reactions of the host against malignant neoplastic cells do occur, it becomes important to consider the effectiveness and the relevance of immunity in suppression or elimination of neoplastic growth. Emphasis is placed on experimental results obtained in syngeneic tumor-host combinations, because they more closely resemble the situation of spontaneous tumorigenesis or leukemogenesis than xenogeneic or allogeneic model systems. Studies of types of neoplasia observed in cases of human immunodeficiency syndromes offer an important insight into problems involved in immunoselection of leukemic cell lines: the marked predominance of leukemias and lymphoreticular neoplasias in immunodeficient patients invites speculation on both the mechanisms of leukemogenesis and the relative importance of the immune system in eliminating malignant neoplastic cells.

Animals↗
PubMed1976

Studies on the regulation of the neutrophil chemotactic response using a rapid and reliable method for measuring random migration and chemotaxis of neutrophil granulocytes.

An economic and sensitive test system for measuring random and directional migration of human neutrophils is described. The technique, based on a modified Boyden chamber equipped with a two-filter system, permits a substantial reduction of both incubation time and sample volume. The influence of various technical factors such as the neutrophil concentration in the cell suspension, the incubation time of the chambers, the test concentration of activated plasma or serum, the presence of heparin, and the procedure for separating neutrophils from human peripheral blood, was investigated. Standardized procedures for measuring and reporting neutrophil chemotaxis are proposed. The method has been used to study the significance of factors regulating neutrophil migration such as cytotaxin inactivators and neutrophil immobilizing factors (NIF). Activity of cytotaxin inactivators as assessed in undiluted serum or plasma at pH 7.4, 6.0 or 4.0 was very low. In contrast, potent neutrophil immobilizing activity was found in human serum or diluted plasma. These factors which inhibit migration were accordingly termed neutrophil immobilizing factors of plasma (NIF-P) and neutrophil immobilizing factor of serum (NIF-S). These factors are heat-stable, non-dialysable and of high molecular weight.

Antigen-Antibody Complex↗
PubMed1976

Monoclonal plasma cell population in the uterus.

The case of a 28-year-old female patient is presented. Heavy infiltration with plasma cells of uterine tissue removed by surgical currettage following an aborted pregnancy was detected by cytological and histological examination. Subsequent immunohistochemical studies revealed the monoclonal nature of these cells: intracellular immunoglobulin contained gamma- and lambda-chains exclusively. Since careful clinical examination produced no evidence in favor of multiple myeloma, these findings were tentatively interpreted to be compatible with the diagnosis of solitary plasmocytoma of the uterus.

Abortion, Habitual↗
PubMed1975

[Testing of granulocyte function].

Recent work on the in-vitro analysis of granulocyte functions is reviewed. Various forms of granulocyte functions defect have been observed in association with increased susceptibility to infectious diseases. Intrinsic cellular defects can be distinguished from secondary impairment of granulocyte functions due to other diseases, iatrogenic causes or humoral defects. In such cases the in-vitro methods for evaluation of granulocyte functions have become an indispensable diagnostic aid.

Blood Bactericidal Activity↗
PubMed1975

[Immunological aspects of gastrointestinal neoplasms].

The mammalian immune system appears to play an essential role in preventing the development, and/or in controlling growth and spread, of malignant tumor cells. Antigenic properties of neoplastic cells and defense mechanism of the tumor host are briefly reviewed. The relative importance of immune reactions and other "non-specific" means of host defense with regard to tumor development and growth are discussed in the light of available experimental and clinical evidence. An attempt is made to incorporate these considerations into a hypothesis relating to the development of intestinal neoplasms.

Antigens, Neoplasm↗
PubMed1975

Nonspecific acid esterase activity: a criterion for differentiation of T and B lymphocytes in mouse lymph nodes.

A modified technique was used to demonstrate lymphocytic acid alpha-naphthyl acetate esterase activity in frozen sections of mouse lymphoid tissue or smears. Positive, dot-like reaction products were noticed in more than 94% of the lymphocytes located in the diffuse cortical ("paracortical", "thymus-dependent") area of mesenteric lymph nodes of young adult ICR mice. Almost identical values were found for lymphocytes in the cisterna chyli. In contrast, the follicular cortex which is predominantly occupied by B cells, contained less than 7% esterase-positive lymphocytes. In vitro, cytotoxic anti-theta serum destroyed the vast majority of esterase positive lymphocytes while esterase-negative lymphocytes were resistent to this treatment. In mesenteric nodes of nude BALB/c (nu/nu) mice, follicular cortex and paracortex together contained approximately 16 times less esterase-positive lymphocytes than in the immunologically competent hybrid BALB/c (nu/+) animals. These findings indicate that non-specific acid esterase activity may serve as a criterion to differentiate peripheral T and B lymphocytes in lymph node sections and smears of mice by light microscopy. Possible implications of this enzyme activity in thymus-derived lymphocytes are discussed.

Animals↗
PubMed1975

Early and enhanced antioxin responses elicited with complexes of tetanus toxoid and specific mouse and human antibodies.

Primary tetanus antitoxin responses were early and enhanced in mice when tetanus toxoid was administered in complex with specific isologous antitoxin or specific mouse gamma-globulin. Antoxin responses were enhanced when fluid tetanus toxoid was complexed in vitro in antigen-to-antibody ratios of equivalence or antigen excess; responses to complexed toxoid in antibody excess were comparatively repressed. Primarly responses were greatly inhibited in mice immunized with the same amount ot toxoid complexed in vitro in antigen-to-antibody ratios of equivalence or antigen excess; responses to complexed toxoid in antibody excess were comparatively repressed. Primary responses were greatly inhibited in mice immunized with the same amount of toxoid complexed at equivalence or in antibody excell with specific human gamma-globulin. Although primary responses. Separate injections of antigen and antibody at different sites produced an excelldnt antitoxin responses. Separate injections of antigen and antibody at different sites produced an excellent in vivo primed state for early and high responses. Antibody production after stimulation with complexed toxoid was also enhanced in mice irradiated with 400 rad, a dose that ordinarily completely suppresses primary responses with fluid toxoid alone. These data provide evidence for the efficacy of antigen-antibody complexes in early and active immunization.

Animals↗
PubMed1975

Thymus lymphocytes. Efflux and restoration phases after peripheral exposure of mice to phytohaemagglutinin.

Juvenile Swiss mice experienced significant diminutions in thymic content of both small, non-proliferating and larger, proliferating lymphocytes within 12 hours after intraperitoneal injection of phytohaemagglutinin. These alterations, which may predate alterations in lymphocyte traffic and morphology elsewhere, were interpreted as being the consequence of a massive thymus lymphocyte emigration, not of in situ cytolysis, and were effaced by intrathymic lymphocyte restoration toward control numbers by 24 hours.

Animals↗
PubMed1975

Physiology of chemotaxis and random motility.

The following aspects of random and directional migration of leukocytes have been considered: (1) basic cellular mechanisms involved in leukocyte locomotion; (2) the mechanisms of formation and the nature of various factors such as cytotaxins, cytotaxin-inactivators and inhibitors participating in the regulation of the chemotactic response, and (3) the relationship between chemotaxis and leukocyte emigration. The need for adequate techniques for measuring chemotaxis has been emphasized with special reference to clinical investigation.

Blood Glucose↗